PDA

View Full Version : Can I make clouds look like sunlight?



ironpony
06-05-2012, 09:56 PM
I shot half a scene which I need to finish. I only have this coming weekend to finish the scene, after that the location will not be available, neither will one of the actors. I have to finish the scene before then, but it was clear sunny skies that day, and it's been raining since. The weather network predicts rain over the weekend. So since it's my last chance I have no choice but to finish the scene with the weather as it is, and try to make it look sunny to match in post. I have to make it also match exactly as the previous shots or at least to the point where the audience won't notice. Can this be done, or what do I do? Thanks.

One of the shots I already have a few takes of are also all cloudy where the rest is sunny, and was wondering if I can fix that too.

nothing
06-06-2012, 12:23 AM
Rent some big HMIs.

ironpony
06-06-2012, 06:29 AM
I considered that but the only rental store in town is out for at least 50 days. I'll check other stores, but need a back up plan, that doesn't rely on renting since you always have to book at least 50 days in advance at the store we have here.

KyranFord
06-06-2012, 06:43 AM
This would probably have to be a 'last resort' type method, but you could hire a VFX artist to mask out the cloudy skies, replace them with the same skies from your other shots, and add light sources to the actors/subjects/objects in the other shots.

bgodoy
06-06-2012, 12:22 PM
As stated, a simple sky replacement would be the solution. However, in all honesty, it would probably be easier to replicate cloudy footage instead of something sunny. It's far more convient for a VFX artist to replicate a darker environment than something lighter in most cases (obviously due to eventual the noise you will get from live action footage while adjusting exposure). The good news is that if you light it right, you (or someone you hire) can have a relatively easy time in post.

Personally, I've done plenty of shots like this before but I have to admit this situation is out of the the ordinary. Post production can only remedy so much if your lighting does not match the footage your trying to emulate, as I'm sure you have already guessed. Here's what I would do:

1.) While shooting, light your scene accordingly. Getting everything just right during production will most likely be the hardest part. I don't specialize in this area but, for starters, I would definitely recommend making sure your "sunlight" is coming from the same place or direction when you last filmed your scene. Preferably, your key light should represent the sun since sunlight is obviously the brightest light source in any scene.

2.) Color correction (before you read on, be aware that Parade scopes or even a good waveform always goes a long way).

A.) Replace your sky with something believable. I've seen really good sky replacements and pretty poor ones too, use a sky that actually fits your scene. Try to copy the cloud formations, amount of clouds, sun/sun direction etc. in your current footage.

B.) Match your shadows. Meaning, if your shadows (or blacks) are tinted more red in your current footage, try and tint the newer footage the same shade. A good way to see what color your blacks are tinted, is by raising your exposure quite a bit until you can clearly see where your shadows tend to lean colorwise. Grain / noise or color profile from your camera usually defines what "tint" your shadows are. When they are tinted the same you can remove the over exposure and get everything back to normal. Keep in mind though, proper exposure is important when reshooting because if your shadows are too dark they won't show up (since they will be basically non existent).

C.) Match saturation. Color grading (separate from color correcting) your footage is best left for the end but it might not be a bad idea to adjust saturation before the final grade. It will make things easier in the end.

3.) Match grain levels if necessary. Meaning match the amount of grain.

4.) Match blur or "perceived quality" of footage with your sky. Since you might end up using a picture with an extremely higher resolution (compared to your video), blurring the still a bit will make your sky sit better in your scene. Matching the level of detail in which your footage is recorded or sharpness is a big one a lot of people miss too. If your sky is too sharp it will give it away. The important thing is realism.

5.) Track your sky if your shoots aren't locked off. I won't go into too much detail here but if the shoot is on a dolly, your sky should follow. Remember though, parallax and perspective should be taken into consideration.

6.) Implement the final grade to bring it all together.

I hope I didn't overdo the explanation there haha. Of course every sky replacement is its own monster but these are steps I see people miss at times. Let us know how it goes.

-B

ironpony
06-06-2012, 04:23 PM
Okay thanks. The scene takes place in a room with a window, and the camera is pointed mainly in two directions. One actors is in front of the window and sunlight is behind him coming in. You can see some on his ear, back of head, and shoulder. The other actor is facing that actor, and is sunlight on his face, and upper body. I don't care really if it's sunny or cloudy in post much, just so long as I can get it all to match. I haven't worked with changing the actual light source in post yet so I have no idea what to do there, but can learn. I just hope it's sunny enough or similar enough.

bgodoy
06-06-2012, 07:45 PM
Well your set up doesn't seem too complicated, I'm assuming it's a typical dialogue scene. In that case, I would suggest adding some sunlight instead of making it cloudy, given the fact that the sun is already serving as a rim light in your current footage.

It might not be a bad idea to invest in some lens flares. They can help mimic the way the sunlight wraps around your subjects relatively quickly and without the need of going through much of a learning curve. Try videocopilot's lens flare package. They're done amazingly well.

Another thing worth mentioning is filming your backgrounds with no subjects (for every angle you intend on using). That way, you might be able to use those shots as "plates" for masking out the window and adding your sunlight (or lens flare) easily.

You can then green screen your actors if you feel up to it. As long as you make sure the angle and camera position is precisely the same for each shot, you could save yourself or your VFX artist a vast amount of roto time.

These are simply ideas. By no stretch of the imagination is this the way to go about it but I'm trying to offer some insight and hopefully save you some time.
-B

ironpony
06-08-2012, 12:21 PM
Okay thanks, but I suck at green screening and was told by others to avoid it at all costs. It just doesn't seem that reliable, in today's standards of convincing the audience. But I was forced to shoot in the rain. The rain is not noticeable, but the lack of sunlight is, coming through the window. So it is possible to fix this with After Effects right? Some of people's solutions with AE are not by professional standards of quality, and I don't want the whole movie to be ruined cause of this one weather snag.

Gord.T
06-08-2012, 03:58 PM
Okay thanks, but I suck at green screening and was told by others to avoid it at all costs.It just doesn't seem that reliable, in today's standards of convincing the audience.

If you suck at it then hire someone who is good. PM me and I'll refer you. It's done all of the time. example from guys here...http://vimeo.com/5124732





But I was forced to shoot in the rain. The rain is not noticeable, but the lack of sunlight is, coming through the window. So it is possible to fix this with After Effects right?

Who sais?


Some of people's solutions with AE are not by professional standards of quality, and I don't want the whole movie to be ruined cause of this one weather snag.

The advice that has been given is plenty help to get it done. There is no magic solution for what you got yourself into.

If you want better responses, hire a VFX company. Again, PM me and I'll refer you.

That's what you have to work with. If you could afford to shoot it right in the first place you wouldn't have this problem.
If you can't afford to shoot it right, this is the s*%t you have to deal with.

I don't mean to sound harsh, chances are you can't fix it without putting in a lot of effort and money if your looking for professional work.

I hope I didn't come across wrong but it is frustrating to hear people expecting miracles from the post guys with a nothing budget.

Rant over.

(I'll help you if I can.)

ironpony
06-10-2012, 12:02 AM
Okay thanks. I might PM you later about it. I actually stuck some blue in the shots, just a hint, but the blue actually makes the cloudy shots match quite well. I can tell the difference but I showed it to one friend so far, and she said she can't so far, so that's good.

Gord.T
06-10-2012, 12:28 PM
Is there any way you can post 2 grabs, 1st from the scene prior to it and 2nd/ the one that has to be fixed?

That's a good idea btw to alter the shots slightly before and after to help match. Good idea.

Good luck.

Let us know how it goes or if you need any help.